The correct lighting plan can improve the vision of the aging eye. As we age, natural changes of the human eye diminish our visual abilities including our ability to read. The cornea becomes more opaque because of increased fat deposits making it more difficult for the eye to recognize the visual images, weaker ciliary muscles and an increased rigidity and hardening of the lens reduce our ability to focus and to adjust to different light levels easily. In dark adapted conditions, the 20 year old eye receives about 16 times more light. In comparison to younger people, it is as though older persons were wearing medium-density sunglasses in bright light and extremely dark glasses in dim light.
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